The characteristics of Autism Spectrum Disorders range widely from individual to individual, but they tend to fall across three different axes. These characteristics cluster around sensory integration, symbols and language and social skills.
Children with Autism Spectrum Disorders seem to process sensory information differently than typically developing individuals.
Sometimes they are hyper-sensitive, and over respond to the simplest sensory input, whether physical, auditory or kinesthetic (whole body orientation or gross body.) These children may scream when overstimulated. It might be a noisy public space (a train station) or a prickly sweater which causes the over-stimulation.
Sometimes, a child is hypo-sensitive, and may go out into the snow barefoot, or may hit him or herself in the head because they need sensory input.
Children on the spectrum may be hyper sensitive to some stimuli, and hypo sensitive to others. A child may hypersensitive to certain kinds of clothing, but may be hypo sensitive to loud noises.
Some children on the spectrum are described as "heavy work," as they need great amounts of sensory input to maintain equilibrium or calm themselves. They can be calmed with a backpack full of books, or may like to be rolled up in a mat and have a teacher lie on top of them. These children respond well to gross motor sensory input, such as swinging, heavy lifting or deep pressure.
Stereotypic behavior such as "stimming" (repetitive action, such as hand flapping) is often a child with autism's effort to create his own sensory stimulation or input.
Occupational Therapists have training and can share strategies that help children on the spectrum deal with sensory input challenges.
Symbols and Language
Difficulty with sensory input also impacts a child's ability to process and understand language, and at the same time symbols. After all, language is a system of auditory symbols.
Parents sometimes report that their children with autism have language when they are infants but lose it when reach two or three. It is possible that these children, who repeated combinations of sounds as infants, with age fail to understand their relationship to social interaction or getting desired objects or attention. They may simply stop producing language.
Language delay is probably one of the most common traits of children on the autism spectrum. Often is related to difficulty with processing auditory information. Sometimes children with autism will never entirely create spoken language, but may have good receptive language (the ability to understand spoken language.)
Children with autism may acquire a vocabulary, they may be able to identify objects but may not be able to understand other important elements of language, such as syntax (how we string words together.) or pragmatics (the relationship of ideas to one another.) Some children never quite get pronouns. They will say "You want a cookie,:" when they mean "I want a cookie." Often they can be taught to use language with intensive speech therapy provided by language and speech pathologists.
Children on the spectrum who develop good speech may still struggle with written language, because they have difficulty with understanding nuance, inferences or the social implications of a narrative. Reading tests designed to measure the ability of typically developing children often provide little meaningful information for a teacher of children on the autism spectrum.
One of the clearest and most consistent characteristic of autism is the lack of understanding of social or social ability. As infants, children with autism lack "joint attention." If an adult drops something on the floor, and looks at it a typically developing child will also look. Children with autism do not.
As children on the spectrum develop, they lack an important precursor of social development, which is "theory of mind." Theory of mind is an understanding that other people are thinking, do have feelings and do respondto what we do or say. A child with autism initially sees parents as their own personal automat: they provide food, goodies and stimulation. As they grow they may use aggression or other inappropriate behavior (such as fecal smearing, removing their clothing) to avoid things they don't want to do and get things they want. They do not understand "good" or "bad" except as sets of activities and the way their parents or other significant adults respond.
As appropriate behavior is modeled and taught, children on the spectrum can become very inflexible, and do not like changes in their routines, largely because they do not have a flexible repertoire of behaviors to respond, and often don't get feedback. When children with autism approach adolescence they begin to want to interact with typically developing peers, but often lack the skill set to do it successfully. This is where teaching social skills becomes so important for functional and academic success for academically capable students.